UFCThe Ultimate Fighting Championship (UFC) is a U.S.-based mixed martial arts organization, recognized as the largest MMA promotion in the world. The UFC is headquartered in Las Vegas, Nevada and is owned and operated by Zuffa, LLC. This promotion is responsible for solidifying the sport's postion in the history-books.
UFC is currently undergoing a remarkable surge in popularity, along with greater mainstream media coverage. UFC programming can now be seen on FOX, FX, and FUEL TV in the United States, as well as in 35 other countries worldwide.

I know he lost to Ryo Chonin (not sure the exact spelling), but who else? His fight record shows four losses.

Just for future reference a lot of the fighters past fights (Results) can be found in the Fighter Info section of this forum. And I feel like a traitor recommending it, but sherdog.com has pretty much every fighters past fights and results you could think of so just go there and search the fighter your looking for